This kit includes the YF-680 12V Compressor, 9.5L (2.5 gallon) air tank, pressure switch, wiring, tubing & fittings. Fill tires, run air jacks, pump up mattresses and inflatable boats in good time, run your ARB air lockers, air bags and train horns, even run small pneumatic air tools all from your 4WD or car. It also comes with the loudest train horn on the market today. It is suitable for 12v & 24v (battery not included). This is the loudest most genuine sounding train horn on the market today, generating in excess of 159db of sound.